A treatise on prayer by a great early Christian theologian from Alexandria. Using prayers from both the Old and New Testament as examples, he creates a primer on what sort of things a Christian should pray for, and how. His primary tool for doing this is a detailed interpretation of the Lord's Prayer.
Date 2007-11-07Source Origen on Prayer, translated by William A. CurtisRun time 4 hrs. 50 min.
Some of the theology, Biblical interpretation, and Christian practice that he advocates has been developed further since his time. So you may need to take these bits with a grain of salt. But much of his advice and insight is still good today, as well as serving as an interesting slice of historical life.